The sheriff’s office said Wednesday they recently arrested 28-year-old Michael Miller on suspicion of the sex assault. Authorities say their investigation and comments Miller has made leads them to believe there may be other victims and they’re hoping they come forward.

“Some of these victims haven’t come forward because they think that they have some ownership for what happened. That they met him, they went on a date with him, they engaged to some degree and then no didn’t actually mean no,” said Jeffco Sheriff spokeswoman Jacki Kelley. “We want to hear from them, we want to know that what we believe did occur involving the suspect is a crime. It is against the law to do what we think he’s done.”

Investigators say Miller is suspected of meeting numerous women on dating sites and other places on the Internet during the past four years. They accuse him of gaining the women’s trust, meeting them for a date, and then using force or intimidation to assault them.

Authorities say the women may be reluctant to report their experience because of embarrassment and confusion about what happened.